title: Pharmacokinetics of single-dose intravenous or intramuscular administration of gentamicin in roosters.
abstract: Healthy mature roosters (n = 10) were given gentamicin (5 mg/kg of body weight, IV) and, 30 days later, another dose IM. Serum concentrations of gentamicin were determined over 60 hours after each drug dosing, using a radioimmunoassay. Using nonlinear least-square regression methods, the combined data of IV and IM treatments were best fitted by a 2-compartment open model. The mean distribution phase half-life was 0.203 +/- 0.075 hours (mean +/- SD) and the terminal half-life was 3.38 +/- 0.62 hours. The volume of the central compartment was 0.0993 +/- 0.0097 L/kg, volume of distribution at steady state was 0.209 +/- 0.013 L/kg, and the total body clearance was 46.5 +/- 7.9 ml/h/kg. Intramuscular absorption was rapid, with a half-life for absorption of 0.281 +/- 0.081 hours. The extent of IM absorption was 95 +/- 18%. Maximal serum concentration of 20.68 +/- 2.10 micrograms/ml was detected at 0.62 +/- 0.18 hours after the dose. Kinetic calculations predicted that IM injection of gentamicin at a dosage of 4 mg/kg, q 12 h, and 1.5 mg/kg, q 8 h, would provide average steady-state serum concentrations of 6.82 and 3.83 micrograms/ml, with minimal steady-state serum concentrations of 1.54 and 1.50 micrograms/ml and maximal steady-state serum concentrations of 18.34 and 7.70 micrograms/ml, respectively.
authors.affiliation: Department of Physiology, College of Veterinary Medicine, Auburn University, AL 36849.
authors.forename: W M
authors.initials: WM
authors.lastname: Pedersoli
authors.forename: W R
authors.initials: WR
authors.lastname: Ravis
authors.forename: D R
authors.initials: DR
authors.lastname: Askins
authors.forename: L M
authors.initials: LM
authors.lastname: Krista
authors.forename: J S
authors.initials: JS
authors.lastname: Spano
authors.forename: J F
authors.initials: JF
authors.lastname: Whitesides
authors.forename: D S
authors.initials: DS
authors.lastname: Tolbert
mesh_terms: D000818:Animals; D002645:Chickens / Q000378:metabolism*; D005839:Gentamicins / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D008297:Male
chemical_list: D005839:Gentamicins